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K. Mitura, M. Jedrzejewska-Szczerska, P. Ceynowa, M. Dudek, M. Cicha, I. Kotela and S. Mitura

Abstract

The purpose of this paper is to present the innovative design of microwave plasma system for modification of detonation nanodiamond particles (DNP) using a special rotating drum placed inside the reactor. Nanodiamond particles manufactured by detonation method reveal the biological activity depending on surface functionalization. Plasmachemical modification of detonation nanodiamond particles gives the possibility of controlling surface of nanodiamonds particles in biological tests. In this paper we would like to compare detonation nanodiamond (the grain sizes from 2 to 5 nm) with modified detonation nanodiamond in rotary reactor chamber, by microwave plasma activated chemical vapour deposition (MW PACVD) method in materials research (Raman and FT-IR spectroscopy) and in vitro examinations with full of human blood. The results indicate haemocompatibility of non-modified detonation nanodiamond and modified nanodiamond by MW PACVD method in rotary reactor chamber (modified ND-3) and the presence of haemolysis in commercial detonation nanodiamond.

Open access

Anukorn Phuruangrat, Budsabong Kuntalue, Titipun Thongtem and Somchai Thongtem

Abstract

Shuttle-like BaMoO4 microstructure has been successfully synthesized from Ba(N03)4H20 and Na2MoO2H2O as starting materials in ethylene glycol solvent containing 20 mL 5 M NaOH by microwave radiation at 180 W for 30 min. The as- synthesized BaMoO4 product was characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, Raman spectrophotometry, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and photolumines­cence (PL) spectroscopy. XRD patterns revealed that the products was tetragonal BaMoO4 phase. SEM and TEM characteriza­tion showed that the product had a shuttle-like BaMoO4 microstructure. PL of the shuttle-like BaMoO4 microstructure showed a maximum emission at 466 nm excited by 280 nm wavelength.

Open access

M. Kutty Pv, S. Dasgupta and S. Bandyopadhyay

Abstract

A new method of preparation of nanocrystalline zinc aluminate (ZnAl2O4) powder is described in this paper. Different organic acids are used as template material and nitric acid as an oxidant. Single phase ZnAl2O4 spinel can be formed at a much lower temperature through this route which gives nanocrystalline powder with uniform particle size and morphology. The powders are characterized by thermo gravimetric analysis (TGA), X-ray diffraction analysis (XRD), Fourier transform infrared spectroscopy (FT-IR), BET surface area analysis and field emission scanning electron microscopy (FE-SEM). The average crystallite size of the single phase material was of 20 to 30 nm and the surface area was found to be 21 to 27 m2g−1.

Open access

Luqman Ali Shah, Murtaza Sayed and Mohammad Siddiq

Abstract

Three dimensional cross-linked polymer microgels with temperature responsive N-isopropyl acrylamide (NIPAM) and pH sensitive methacrylic acid (MAA) were successfully synthesized by free radical emulsion polymerization with different amounts of MAA. Silver and gold nanoparticles with the size of 6.5 nm and 3.5 nm (±0.5 nm), respectively were homogeneously reduced inside these materials by chemical reduction method at pH 2.78 and 8.36 for the preparation of hybrid materials. The samples were characterized by FT-IR, DLS and TEM techniques. The catalytic activity of the hybrid materials was investigated for the reduction of 4-nitrophenol (4-NP) using NaBH4 as reducing agent by UV-Vis spectroscopy. The hybrid polymer network synthesized at pH 8.36 showed enhanced catalytic efficiency compared to the catalysts synthesized at pH 2.78. In this study, it has been stated that the catalyst activity strongly depends on the amount of MAA, pH value during synthesis and the type of entrapped metal nanoparticles.

Open access

Neeraj K. Mishra, Chaitnaya Kumar, Amit Kumar, Manish Kumar, Pratibha Chaudhary and Rajeev Singh

Abstract

A nanocomposite of 0.5SnO2–0.5Al2O3 has been synthesized using a sol-gel route. Structural and optical properties of the nanocomposite have been discussed in detail. Powder X-ray diffraction and scanning electron microscopy with energy-dispersive X-ray diffraction spectroscopy confirm the phase purity and the particle size of the 0.5SnO2–0.5Al2O3 nanocomposite (13 to 15 nm). The scanning electron microscopy also confirms the porosity in the sample, useful in sensing applications. The FT-IR analysis confirms the presence of physical interaction between SnO2 and Al2O3 due to the slight shifting and broadening of characteristic bands. The UV-Vis analysis confirms the semiconducting nature because of direct transition of electrons into the 0.5SnO2–0.5Al2O3 nanocomposites.

Open access

Nitin R. Dighore, Priyanka L. Anandgaonker, Suresh T. Gaikwad and Anjali S. Rajbhoj

Abstract

Crystalline MoO3 nanoparticles were obtained by electrochemical synthesis process using tetrapropylammonium bromide as a stabilizer and structure-directing agent in ACN:THF(4:1) solvent. Formation of MoO3 nanoparticles took place at a constant supply current of 14 mA/cm2. These synthesized MoO3 nanoparticles were characterized by UV-Vis spectroscopy, FT-IR spectroscopy, powder X-ray diffraction (XRD), scanning electron microscopy (SEM). So prepared MoO3 nanoparticles were used as a heterogeneous catalyst for the synthesis of 2,6-bis(benzylidene)cyclohexanone derivatives. This protocol offers several advantages, such as simple work-up procedure, recyclability of the catalyst, excellent product yield in a short reaction time and purification of products with a non-chromatographic method.

Open access

Shuiping Li, Qisheng Wu, Chong Cui, Guosen Lu, Changsen Zhang and Zhiye Yan

Abstract

TiO2/Al-MCM-41 mesoporous materials were prepared via sol-gel method by loading titania onto Al-MCM-41 mesoporous molecular sieve by hydrothermal treatment from coal-series kaolin as raw material. The TiO2/Al-MCM-41 mesoporous materials were characterized by XRD, FT-IR, HRTEM, N2 adsorption-desorption and the photocatalytic degradation of methyl orange solution under visible light irradiation. The results showed that the TiO2/Al-MCM-41 mesoporous materials possessed a high surface area of 369.9–751.3 m2/g and a homogeneous pore diameters of 2.3–2.8 nm. The titania crystalline phase was anatase, and the particles size of TiO2 increased with TiO2 content. The Al-MCM-41 mesoporous materials exhibited excellent photodegradation activity under visible-light irradiation for methyl orange.

Open access

Yifu Zhang

Abstract

Coordination of vanadyl (VO2+) ions with 8-hydroxyquinoline (8Hq) in the interlayer space of layered silicate magadiite (mag) was realized by solid-solid intercalation. Composition, structure and morphology of this compound were studied by X-ray diffraction (XRD), Fourier-transform infrared spectrometry (FT-IR), scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDS), X-ray photoelectron spectroscopy (XPS) and inductively coupled plasma atomic emission spectroscopy (ICP-AES). The obtained results indicate that the basal spacing of decorated mag increased after intercalation and suggest that VO-8Hq decorated into the interlayer of mag (VO-mag-8Hq) was successfully synthesized for the first time. Optical properties of VO-mag-8Hq were studied by ultraviolet-visible (UV-Vis) and photoluminescence spectroscopy (PL). The findings reveal that VO-8Hq complexes in the interlayer space exhibit extraordinary fluorescence properties and the confined space of mag influences the optical properties of VO-8Hq complexes.

Open access

Atieh Aliakbari, Majid Seifi, Sharareh Mirzaee and Hoda Hekmatara

Abstract

In the present paper, iron oxide nanoparticles coated by oleic acid have been synthesized in different conditions by coprecipitation method. For investigating the effect of time spent on adding the oleic acid to the precursor solution, two different processes have been considered. The as synthesized samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FT-IR). Magnetic measurement was carried out at room temperature using a vibrating sample magnetometer (VSM). The results show that the magnetic nanoparticles decorated with oleic acid decreased the saturation of magnetization. From the data, it can also be concluded that the magnetization of Fe3O4/oleic acid nanoparticles depends on synthesis conditions.

Open access

B. Punithaveni, K. Thilagavathy, N. Muthukumarasamy, D. Nithyaprakash and M. Saravanabhavan

Abstract

New organic single crystals of 2-amino-6-methylpyridinium 2-hydroxybenzoate (2A6M2H) were grown by slow evaporation solution growth technique at room temperature. The grown crystal structure was studied using single crystal XRD. Crystalline nature and phases were confirmed by powder XRD analysis. FT-IR study was used to identify the functional groups present in the compound. UV-Vis study revealed that the lower cut off wavelength of the crystal is at 350 nm. The dielectric studies indicated the low value of dielectric loss at high frequency. Mechanical properties of the crystals were studied using Vickers microhardness test. The Z-Scan studies were conducted for the crystal using He–Ne laser.